Refrigerating apparatus



w. GIFFARD ,387,840

REFRIGERATING APPARATUS 3 Filed Sept. 15, 1945 2 Sheets-Sheet 2 Patented Oct. 30, 1945 2,387,840 REFRIGERATING APPARATUS Whitney emai s, Detroit, Mich, assignor to Nash- Kelvlnator Corporation, Detroit, Mich, a corporation of Maryland Application September 13, 1943, Serial No. 502,136

Claims.

This invention relates to refrigerating apparatus and, more particularly to refrigerating apparatus of the multiple temperature type.

One of the objects of my invention is to provide an improved refrigerating apparatus for maintaining a plurality of zones at difierent temperatures and different relative humidities.

Another object of my invention is to provide an improved refrigerating apparatus which comprises a refrigerator cabinet having its interior divided into two upper compartments and a lower compartment, one of said upper compartments being refrigerated to sub-freezing temperatures by means of a low temperature primary refrigerant evaporator, while the other upper compartment is refrigerated by said primary evaporator and said other upper compartment and the lower compartment is refrigerated by a high temperature refrigerant evaporator.

Another object of my invention is to provide an improved refrigerating apparatus wherein the cabinet interior is divided into an upper low temperature freezing zone and an upper high humidity zone and a lower intermediate temperature and intermediate humidity zone, the high temperature high humidity zone being in communication with the intermediate temperature and humidity zone which in turn is arranged in communication with the low temperature freezing zone.

Further objects and advantages of the present invention will beapparent from the following description, reference being had to the accompanying drawings, wherein a preferred form of the present invention is clearly shown.

In the drawings:

Fig. 1 is a front view partly in elevation and partly in cross section of my improved refrigerating apparatus;

Fig. 2 is a view taken along the'line 2-2 of Fig. 1;

Fig. 3 is a view taken along the line 3-3 of Fig. 1;

Fig. 4 is a view taken along the line 4-4 of Fig. 1;

Fig. 5 is a view partly in cross section and partly in elevation of the primary secondary heat exchanger employed in my improved refrigerating apparatus; and

Fig. 6 is a view in perspective of a portion of my improved refrigerating apparatus.

In accordance with my invention, I have provided an improved refrigerating apparatus which comprises a cabinet having its interior divided into two upper compartments and a lower compartment which are separated from each other preferably by glass partitions. One of the upper compartments is refrigerated at a low temperature, preferably freezing or lower, by means of a primary evaporator of a primary refrigerating system, which is adapted also to freeze ice cubes and the like. The other upper compartment and the lower compartment are refrigerated by means of a secondary evaporator of a secondary system which is arranged in heat exchange relation with a portion of the primary system. The secondary evaporator is arranged in heat exchange relation with two walls of the second upper compartment so as to provide a relatively high temperature and high humidity zone therein. One wall of the second upper compartment is cooled by the primary evaporator. The lower compartment, on the other hand, is preferably refrigerated by the secondary evaporator on all possible sides so as to provide a zone having temperature and a relative humidity intermediate the temperatures and relative humidities of the two upper compartments. A limited circulation of air between the high humidity compartment and the lower compartment is provided in the partition therebetween while a limited circulation of air is also provided between the freezing compartment and the lower intermediate temperature compartment. By this arrangement, applicant has provided a refrigerator cabinet having three zones of temperatures and relative humidities by the placement with respect to each other of each of the three compartments. The high temperature high humidity compartment is placed to one side of the freezing compartment so that the cooling effect of the low temperature compartment is minimized with no direct circulation of air between the two compartments being permitted. Furthermore, the high temperature compartment is placed above the intermediate temperature and humidity compartment with which it is in limited communication so that there is little natural tendency of the lower temperature air in the lower compartment to difiuse into the upper high humidity compartment. Excessive precipitation of moisture within the high humidity compartment is avoided by the limited circulation of air permitted between the two humidity compartments and between the intermediate humidity compartment and the low temperature compartment. Thus it will be seen that applicant has provided a plurality of food storage compartments which are effectively maintained at different temperatures and different relative humidities.

' Referring to the drawings, numeral 20 designates a refrigerator cabinet having a food compartment 2| and a machine compartment 22. An

outer lining creasing member 28 and an inner lining member 24 with insulation 28 interposed therebetween are arranged to form a top wall 28, sidewalls 88 and 82, bottom wall 34 and rear wall 86. A door 48 provides access to the compartment 2I while a tiltable door 42 having vegetable bin 44 attached thereto is provided for allowing access to the machine compartment 22. The inner lining member 24 forms the walls of the food storage compartment 2I, which is divided into three compartments 58, 52 and 54 by means of a vertical sealing partition 55 and a horizontal partition 58. These partitions are preferably made deemed desirable. of the evaporator 88 is suiilciently low to provide of some non-heat conducting material such as glass. The partition 58 is preferably spaced somewhat from the walls of the inner lining member 24 as at 58 so as to permit some circulation of air between the upper compartments and the lower compartment 54. Glass shelves 68 are pro-.

vided in compartment 52 and another glass shelf 62 is provided in compartment 58. These shelves are preferably spaced from the walls of the compartments to permit circulation of air within the compartments. A door 68 which is preferably of some metallic material serves to complete the isolation of compartment 58 and to permit access thereto. Another door I8, preferably having a glass pane, completes the isolation of compartment 52 and permits access thereto. This door prevents loss of refrigerated air in compartment 52 when door 48 is opened and tends to maintain certain high humidity conditions in compartment 52.

A primary refrigerant evaporator 88 is provided in compartment 58 for maintaining freezing and subfreezing temperatures therein and also for freezing ice cubes and the like within its confines. Thi evaporator includes a serpentine conduit 82 attached to the under side of a shelf 84 and an L-shaped flooded refrigerant evaporating section 88 having an inlet header 88 and an outlet header 88 connected by refrigerant passages 82. These two sections are arranged in a c-shaped conformation and supported from the top wall of the cabinet by means of two vertical metal plates 98 and 88. A shelf I88 is also supported by these vertical walls between the upper and lower sections of the C-shaped evaporator for supporting ice pans and the like. Liquid refrigerant is supplied to the C-shaped evaporator 88 by a condensing unit II8 located in the machine compartment 22. This unit comprises a sealed motor compressor unit II2 of the well known type anda condenser H4 connected to the discharge side of the compressor by means of a conduit I I6. The motor compressor unit is resiliently supported upon a raised platform II8 from which is suspended in a tilted position the condenser II4. An opening I28 is provided in the bottom of the machine compartment 22 and a flue I22 is provided at the back of the machine compartment. The condensing unit is cooled by the natural flow of air up through the opening I28 over the condensing unit and out the flue which enhances the natural convection effect in-' duced by the heated sections of the condensing unit. The liquid refrigerant is conducted by a small diameter tube I24 up the back of the refrigerator cabinet into a removable portion I38 of the cabinet where it joins a somewhat larger tube I32 which serves as part ofthe primary secondary heat exchanger to be described below. From this tube the liquid refrigerant is conducted by conduit I34 to the serpentine section 82 of the c-shaped evaporator. After circulating through the evaporator the evaporated refrigerant is returned to the condensing unit by a conduit I46 which is preferably arranged in heat exchange relation with the small diameter tube I24. This latter tube serves to control the flow of liquid refrigerant from the condensing unit to the evaporator in a manner now well understood in the art. The operation of this primary refrigerating system is preferably under the control of a thermostatically operated device (not shown) the thermostat control element bein located in any one of the three. compartments wherever it is Preferably, the temperature a rapid freezing zone within its confines and a low temperature zone in compartment 58 for the storage of meats, fish and the like. For this purpose a receptacle I44 is provided between the partition 58 and a shelf 82, the latter shelf serving to restrict the dehydration of the contents of the receptacle as a result of the freezing temperatures existing on the surface of the evaporator 88.

,A secondary refrigerating system I58 is provided for cooling the compartments 52 and 54 which it is desired to maintain at relatively high but different relative humidities. This secondary system includes a secondary evaporator I52 and a secondary condenser I54. The secondary evaporator consists of a serpentine conduit arranged in two sections I54 and I56. Section I54 is secured to the outside of the inner lining member 24 which encloses the compartment 54 while the section I56 is secured to the outside of the inner lining member 24 which partially encloses the compartment 52. The secondary condenser I54 comprises a cylindrical tank I55 to which is directly secured the enlarged conduit I32 of the primary system by means of a metallic sleeve member I68. This heat exchanger is embedded in insulation I62 which is further encased in a rubber sleeve member I84. In operation, evaporated refrigerant from the upper section I58 of the secondary evaporator is conducted to the condenser I54 by a conduit I88 which protrudes up into the cylindrical tank. The evaporated refrigerant is condensed and returned to the lower section I54 by means of a conduit I88. This conduit I88 is shielded from the evaporating conduits by a slab of insulation material I18. The liquid refrigerant then circulates up through the lower section I54 to the cool compartment 54 to a temperature above that of compartment 58 and preferably above the freezing point. Unevaporated liquid refrigerant and evaporated refrigerant circulate upwardly through the serpentine conduit of the secondary evaporator into the upper section I56 to cool the compartment 52. Due to the fact that only two outside vertical wall of this compartment are cooled and also to the fact that the section I58 is the outlet section of the secondary evaporator, only a limited cooling of the compartment 52 is accomplished by coil I58. Additional cooling takes place by evaporator 88 by convection currents in compartment 58. These convection currents cause air in compartment 58 to contact wall 58. However, wall 58 is made of plate glass and does not aid materially in cooling compartment 52 whereby a temperature above that maintained in compartment 54 is provided therein. With door I8 a higher relative humidity is maintained in compartment 52 than compart- 'ment 54. Since it is desirable to have a certain degree of air circulation throughout the entire interior of the compartment 2| limited communication as mentioned before is provided between compartment 52 and compartment 54 and .between compartment 54 and compartment 50 whereby not only is this desirable circulation attained, but also excessive deposition of moisture within the high humidity compartments is avoided without the temperatures desired in the several compartments being appreciably affected. This circulation allows the moisture from high humidity compartment to move to the freezing compartment where it is frozen out of the circulatlngalr on the evaporator 80.

It will thus be seen from the foregoing that I have provided a particularly effective arrangement of several food storage compartments with respect to each other so as to establish zones having sharply delineated temperatures and relative humidities.

Although only a preferred form of the invention has been illustrated, and that form described in detail, it will be apparent to those skilled in the art that various modification may be made therein without departing from the spirit of the invention or from the scope of the appended claims.

I claim:

l. Refrigerating apparatus comprising, in combination, an insulated cabinet having its interior divided into two upper compartments and a lower compartment by a vertical partition and a horizontal partition, said horizontal partition being arranged to allow a limited circulation of air between the upper compartments and the lower compartment, refrigerant evaporator disposed in one of said upper compartments to provide a freezing zone therein, and a second refrigerant evaporator arranged in heat exchange relation with the other upper compartment and with said lower compartment to provide a high temperature high humidity zone in said other upper compartment and an intermediate temperature and humidity compartment zone in said lower compartment.

2. Refrigerating apparatus comprising, in combination, an insulated cabinet having it interior divided into two upper compartments and a lower compartment by a vertical partition and a horizontal partition, a refrigerant evaporator disposed in one Of said upper compartments to provide a freezing zone therein, and a second refrigerant evaporator having a portion thereof arranged in heat exchange relation with said lower I sulated cabinet having its interior divided into three compartments by partition members allowing limited circulation from the first to the third compartments through the second compartment, refrigerant evaporating means associated with said three compartments, said compartments being arranged and evaporating means being positioned to refrigerate said third compartment below the freezing point of water and maintain the air therein at a relatively low humidity, said first compartment at a relatively high humidity and temperature, and the second compartment at intermediate humidity and temperature.

4. Refrigerating apparatus comprising an insulated cabinethaving its interior divided into two compartments with limited air circulation therebetween, a second partition dividing one of said compartments into twozones, refrigerating means for cooling one of said zones to relatively low temperatures and relatively low humidity, refrigerating means for cooling said other zone to relatively high humidity and temperatures and the undivided compartment to intermediate temperatures and humidity conditions.

5. Refrigerating apparatus comprising a cabinet having an inner liner, partition means cooperating with said liner to divide the cabinet into two compartments, additional partition means cooperating with said first named partition means and said liner to divide one of said compartments into sub compartments, a refrigerant evaporating element adapted to cool one of said sub compartments below the freezing point of water, refrigerant evaporating means arranged in contact with the exterior walls of said liner adjacent said other sub compartment and said undivided compartment for absorbing heat therefrom, and closure means for said sub compartments.

WHITNEY GIFFARD. 

